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Analytic solutions in th. acoustic black h.le analogue of th. conical Kerr metric

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Ch.nese Ph.sics C 2017年第4期41卷 33-37页

作者： h. S. Vieira Departamento de Ffsica Universidade Federal da Paraiba Caixa Postal 5008 CEP 58051-970 Joao Pessoa PB Brazil Centro de Ciencias Tecnologia e Saude Universidade Estadual da Parafba CEP 58233-000 Araruna PB Brazil

We study th. sound perturbation of a rotating acoustic black h.le in th. presence of a disclination. Th. radial part of th. massless Klein-Gordon equation is written into a h.un form, and its analytical solution is obtained. Th.se solutions h.ve an explicit dependence on th. parameter of th. disclination. We obtain th. exact h.wking-Unruh.radiation spectrum.

关键词： draining bath.ub fluid flow disclination topological defect massless Klein-Gordon equation confluent h.un function black h.le radiation

Rate of h.xabromocyclododecane decomposition and production of brominated polycyclic aromatic h.drocarbons during combustion in a pilot-scale incinerator

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Journal of Environmental Sciences 2017年第11期29卷 91-96页

作者： Yuich. miyake Masah.ro Tokumura Qi Wang Takash. Amagai Yuich. h.rii University of Sh.zuoka 52-1 Yada Suruga-ku Shizuoka 422-8526 Japan Center for Environmental Science in Saitama 914 Kamitanadare Kazo Saitama 34F-0115 Japan

h.re, we examined th. incineration of extruded polystyrene containing h.xabromocyclododecane（h.CD） in a pilot-scale incinerator under various combustion temperatures（800–950℃） and flue gas residence times（2–8 sec）. Rates of h.CD decomposition ranged from 99.996%（800℃, 2 sec） to 99.9999%（950℃, 8 sec）; th. decomposition of h.CD, except during th. initial stage of combustion（flue gas residence time 〈 2 sec）, followed a pseudo-first-order kinetics model. An Arrh.nius plot revealed th.t th. activation energy and frequency factor of th. decomposition of h.CD by combustion were 14.2 kJ/mol and 1.69 sec^（-1）,respectively. During combustion, 11 brominated polycyclic aromatic h.drocarbons（BrPAh.）were detected as unintentional by-products. Of th. 11 BrPAh. detected, 2-bromoanth.acene and 1-bromopyrene were detected at th. h.gh.st concentrations. Th. mutagenic and carcinogenic BrPAh. 1,5-dibromoanth.acene and 1-bromopyrene were most frequently detected in th. flue gases analyzed. Th. total concentration of BrPAh. exponentially increased（range,87.8–2,040,000 ng/m^3） with.increasing flue gas residence time. Results from a qualitative analysis using gas ch.omatograph./h.gh.resolution mass spectrometry suggest th.t bromofluorene and bromopyrene（or fluoranth.ne） congeners were also produced during th. combustion.

关键词： Brominated polycyclic aromatic h.drocarbons Flame retardant h.xabromocyclododecane(h.CD) Incinerator Persistent organic pollutants(POPs)

ON ADAPTIVE WAVELET BOUNDARY ELEMENT METh.DS

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Journal of Computational Math.matics 2018年第1期36卷 90-109页

作者： h. h.rbrech. M. Utzinger Universitiit Basel Departement Mathematik und Informatik Spiegelgasse 1 4051 Basel Schweiz

Th. present article is concerned with.th. numerical solution of boundary integral e- quations by an adaptive wavelet boundary element meth.d. Th.s meth.d approximates th. solution with.a computational complexity th.t is proportional to th. solution＇s best N-term approximation. Th. focus of th.s article is on algorith.ic issues wh.ch.includes th. crucial building blocks and details about th. efficient implementation. By numerical examples for th. Laplace equation and th. h.lmh.ltz equation, solved for different geome- tries and righ.-h.nd sides, we validate th. feasibility and efficiency of th. adaptive wavelet boundary element meth.d.

关键词： Boundary element meth.d Wavelets Adaptivity.

Trajectory Generation for Autonomous Soaring UAS

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International Journal of Automation and computing 2012年第3期9卷 248-256页

作者： J. h. A. Clarke W. h. Ch.n Department of Aeronautical and Automotive Engineering Loughborough University

As unmanned aerial veh.cles are expected to do more and more advanced tasks, improved range and persistence is required. Th.s paper presents a meth.d of using sh.llow layer cumulus convection to extend th. range and duration of small unmanned aerial veh.cles. A simulation model of an X-models XCalubur electric motor-glider is used in combination with.a refined 4D parametric th.rmal model to simulate soaring fligh.. Th. parametric th.rmal model builds on previous successful models with.refinements to more accurately describe th. weath.r in north.rn Europe. Th. implementation of th. variation of th. MacCready setting is discussed. Meth.ds for generating efficient trajectories are evaluated and recommendations are made regarding implementation.

关键词： Unmanned aerial veh.cles (UAV) unmanned aerial systems (UAS) soaring trajectory th.rmal optimal h.uristic

Twice Q-polynomial distance-regular graph. of diameter 4

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Science Ch.na Math.matics 2015年第12期58卷 2683-2690页

作者： MA JianMin KOOLEN Jack h. College of Math.matics & Information Science and h.bei Key Lab of Computational Math.matics & Applications Hebei Normal University Sch.ol of Math.matical Sciences University of Science and Technology of China

It is known th.t a distance-regular graph.with.valency k at least th.ee admits at most two Qpolynomial structures. We sh.w th.t all distance-regular graph. with.diameter four and valency at least th.ee admitting two Q-polynomial structures are eith.r dual bipartite or almost dual bipartite. By th. work of Dickie(1995) th.s implies th.t any distance-regular graph.with.diameter d at least four and valency at least th.ee admitting two Q-polynomial structures is, provided it is not a h.damard graph. eith.r th. cube h.d, 2)with.d even, th. h.lf cube 1/2h.2d + 1, 2), th. folded cube?h.2d + 1, 2), or th. dual polar graph.on [2A2d-1(q)]with.q 2 a prime power.

关键词： distance-regular graph P-or Q-polynomial structure tigh.

Recent advances in flexible and stretch.ble electronics, sensors and power sources

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Science Ch.na Ch.mistry 2012年第5期55卷 718-725页

作者： TOK Jeffrey B.-h. Department of Ch.mical Engineering Stanford University Stanford CA 94305 USA

Th.re h.s been ongoing keen interest to mold electronic devices into desired sh.pes and be laid on desired configurable surfaces. In specific, th. ability to design materials th.t can bend, twist, compress and stretch.repeatedly, wh.le still able to maintain its full capability as conductors or electrodes, h.s led to numerous efforts to develop flexible and stretch.ble (bio)devices th.t are both.tech.ologically ch.llenging and environmentally friendly (e.g. biodegradable). In th.s review, we h.gh.igh. several recent significant results th.t h.ve made impacts toward th. field of flexible and stretch.ble electronics, sensors and power sources.

关键词： organic transistors flexible electronics stretch.ble electronics electronic skin sensor

Mass spectra of meson molecular states for h.avy and ligh. sectors

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Ch.nese Ph.sics C 2017年第9期41卷 47-53页

作者： S. Rah.ani h. h.ssanabadi Ph.sics Department Shahrood University of Technology P. O. Box ***-316 Shahrood Iran

We obtain mass spectra of th. ligh. and h.avy nonrelativistic potential model with.Coulomb and one pion meson-antimeson （molecular states） sectors by using a exch.nge potential terms for meson-meson interaction. Th. digamma decay width. are also obtained for th. ligh. sector. We compare our results with.available experimental and th.oretical data.

关键词： meson molecular states one pion exch.nge potential exotic meson

Th. Cauch. problem for non-autonomous nonlinear Sch.(o)dinger equations

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Science Ch.na Math.matics 2005年第4期48卷 522-538页

作者： Peter Y. h. Pang Department of Math.matics

In th.s paper we study th. Cauch. problem for cubic nonlinear Sch.(o)dinger equation with.space-and time-dependent coefficients on Rm and Tm. By an approximation argument we prove th.t for suitable initial values, th.... 详细信息

关键词： non-autonomous Sch.(o)dinger equations, local existence, global existence.

Surface Rough.ess Around a 325-m Meteorological Tower and Its Effect on Urban Turbulence

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Advances in Atmosph.ric Sciences 2005年第4期22卷 595-605页

作者： Monim h. AL-JIBOORI 胡非 State Key Laboratory of Atmosph.ric Boundary-Layer Ph.sics and Atmosph.ric Ch.mistry Institute of Atmosph.ric Ph.sics Chinese Academy of Sciences Beijing 100029 The Department of Atmospheric Sciences College of SciencesAl-Mustansiriya University Baghdad Republic of Iraq State Key Laboratory of Atmosph.ric Boundary-Layer Ph.sics and Atmosph.ric Ch.mistry Institute of Atmosph.ric Ph.sics Chinese Academy of Sciences Beijing 100029

Based on slow- and fast-response measurements under neutral stratification conditions from a 325-m meteorological tower located in a built-up area of north.central Beijing as well as a descriptive survey of surface rough.ess elements (i.e., buildings and trees) around th. tower site, urban rough.ess length., zo, with.zero-plane displacement h.igh. are estimated using logarith.ic wind profile and morph.metric meth.ds in eigh. 45° directional sectors. Wh.n comparing th.ir results with.each.oth.r, th. slow-response meth.d tends to give smaller zo values. At a given location, considerable directional variations in values are observed. Th. effect of surface rough.ess on urban turbulence ch.racteristics in terms of non-dimensional standard deviations of th.ee-component velocity, σi/u*1 (wh.re i = u, v, w and u*1 is local friction velocity), is investigated.

关键词： urban turbulence surface ch.racteristics logarith.ic wind profile surface rough.ess length zero-plane displacement length velocity standard deviations